Quick answer
Galvanised pipe, standard in pre-1980s Johannesburg homes, rusts from the inside out. The bore narrows progressively and sheds flakes that block aerators, cartridges and appliance inlet valves. If pressure has dropped across the house, rusty water appears, or fittings keep clogging, the pipe is telling you it is at end of life. Replacement is with copper or PEX.
Common causes
- Internal corrosion progressively narrowing the pipe bore
- Pinhole failure once the wall thickness is compromised
- Rust flakes shedding into the flow and blocking fittings downstream
- Galvanic corrosion where galvanised pipe meets copper without a dielectric fitting
- Threaded joints corroding faster than the pipe runs themselves
- Decades of hard water accelerating internal scaling on top of the corrosion
What you can do now
- 1Check whether rusty water appears on first draw in the morning, which is the classic sign
- 2Note whether aerators and appliance filters keep clogging with rust flakes
- 3Compare pressure now against what it used to be — gradual decline across the house is diagnostic
- 4Look at exposed pipe runs for rust staining at the threaded joints
- 5Plan re-piping around renovations rather than as an emergency
When to call a professional
Re-pipe room by room during renovations rather than waiting for a failure — a full re-pipe on a three-bedroom home is a substantial job and doing it in planned stages spreads both cost and disruption. Call for an assessment as soon as rusty water or falling pressure appears across multiple fixtures, because pinhole failures in galvanised pipe tend to arrive in clusters.
Typical cost in Johannesburg
R25,000–R60,000 full re-pipe
Indicative ranges only. We provide written, itemised quotes before any work.
Related services
Need a Plumber or Electrician Today?
Owner-managed by Garth Blair. We pick up the phone and book you in personally.